Need some advice on containers as tanks

So my (thankfully) nano aquarium cracked, and I was able to transfer everything to a 50 litre storage bin. (Ignore the towel on the ground, I'm paranoid right now) Would this hold long term? Its only filled a bit above halfway but it is on wheels (The bottom has a grid to keep it sturdy, but only the wheels are actually touching the ground). Do I need to upgrade soon? Because I'm not in the best financial spot right now lol